Class of nitrogen-containing heterocyclic polymers, a class of polymer membranes and applications thereof

Abstract

The present invention discloses a class of nitrogen-containing heterocyclic polymers, a class of polymer membranes and applications thereof, wherein the nitrogen-containing heterocyclic polymers comprise structural units of following general formula:A nitrogen-containing heterocycles in the class of nitrogen-containing heterocyclic polymers have large steric hindrance and electron donating groups, which are beneficial for further improving stability of materials. The class of nitrogen-containing heterocyclic polymers can be formed membranes using commonly industrial methods such as coating. The prepared polymer membranes have advantages such as large scale, thin thickness, high strength, and excellent ion conductivity, which can be used in fuel cells, water electrolysis hydrogen production, metal-air batteries, flow batteries, carbon dioxide reduction, supercapacitors, electrodialysis, water treatment, membrane humidification, nickel hydrogen batteries, zinc manganese batteries, acid separation, salt lake lithium extraction, and other fields.

What is claimed is: 
     
       1. A class of nitrogen-containing heterocyclic polymers, wherein comprising a following general structural unit: 
       
         
           
           
               
               
           
         
         R 1  and R 2  are respectively hydrogen atom, methyl group, ethyl group, trifluoromethyl group, pyridyl group, phenyl group, o-methylphenyl group, m-methylphenyl group, p-methylphenyl group or mesitylene group; a is any integer greater than or equal to 1; b is any integer greater than or equal to 0; and 
         A group is selected from following structural formulas: 
       
       
         
           
           
               
               
           
         
         wherein, B group is a nitrogen-containing heterocycle and is selected from following structural formulas: 
       
       
         
           
           
               
               
           
         
         R 3  is a hydrogen atom, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, cyclopropyl group, isopropyl group, isobutyl group, tert butyl group, cyclopentyl group, cyclohexyl group, or N, N, N-trimethylpentamine group; and 
         When both A and B are multiple groups, a combination of A and B in A-B is random, and an arrangement of different combinations is also random. 
       
     
     
       2. The nitrogen-containing heterocyclic polymers according to  claim 1  are prepared by following methods, wherein in presence of an acid catalyst, a nitrogen-containing heterocyclic monomer C undergoes a Friedel-Crafts reaction with an aromatic monomer D, and the nitrogen-containing heterocyclic polymers are obtained; and the nitrogen-containing heterocyclic monomer C is one or more combinations of 
       
         
           
           
               
               
           
         
         the aromatic monomer D is one or more combinations of benzene, biphenyl, 4,4-dimethylbiphenyl, fluorene, 9,9-dimethylfluorene, para-triphenyl, meta-triphenyl, ortho-triphenyl, diphenylmethane, 1,2-diphenylethane, 1,3-diphenylpropane, para-xylene dimer, 2.2-bis (3.4-dimethylphenyl) hexafluoropropane, 2,3-dimethyl-2,3-diphenylbutane, and 1,2-di (1-naphthyl) ethane. 
       
     
     
       3. The nitrogen-containing heterocyclic polymers according to  claim 1  are prepared by following methods, wherein in presence of an acid catalyst, a nitrogen-containing heterocyclic monomer C, an aromatic monomer D, and a ketone monomer E undergo a Friedel-Crafts reaction, and the nitrogen-containing heterocyclic polymers are obtained;
 the nitrogen-containing heterocyclic monomer C is one or more combinations of 
 
       
         
           
           
               
               
           
         
       
       the aromatic monomer D is one or more combinations of benzene, biphenyl, 4,4-dimethylbiphenyl, fluorene, 9,9-dimethylfluorene, para-triphenyl, meta-triphenyl, ortho-triphenyl, diphenylmethane, 1,2-diphenylethane, 1,3-diphenylpropane, para-xylene dimer, 2,2-bis (3,4-dimethylphenyl) hexafluoropropane, 2,3-dimethyl-2,3-diphenylbutane, and 1,2-di (1-naphthyl) ethane; and
 the ketone monomer E is selected from one or more combinations of following structures: 
 
       
         
           
           
               
               
           
         
         R 1  and R 2  are respectively hydrogen atom, methyl group, ethyl group, trifluoromethyl group, pyridine group, phenyl group, o-methylphenyl group, m-methylphenyl group, p-methylphenyl group or mesitylene group. 
       
     
     
       4. The nitrogen-containing heterocyclic polymers according to  claim 1  are prepared by following methods, wherein in presence of an acid catalyst, a nitrogen-containing heterocyclic monomer C, an aromatic monomer D, and an aromatic crosslinking agent monomer F undergo a Friedel-Crafts reaction, and the nitrogen-containing heterocyclic polymers are obtained; and
 the nitrogen-containing heterocyclic monomer C is one or more combinations of 
 
       
         
           
           
               
               
           
         
       
       the aromatic monomer D is one or more combinations of benzene, biphenyl, 4,4-dimethylbiphenyl, fluorene. 9,9-dimethylfluorene, para-triphenyl, meta-triphenyl, ortho-triphenyl, diphenylmethane, 1.2-diphenylethane, 1,3-diphenylpropane, para-xylene dimer, 2,2-bis (3,4-dimethylphenyl) hexafluoropropane, 2,3-dimethyl-2,3-diphenylbutane, and 1,2-di (1-naphthyl) ethane; and 
       the aromatic crosslinking agent monomer F is one or more combinations of triphenylmethane, 1,3,5-triphenylbenzene, triptycene, 9,9′-spirobifluorene, tetraphenyl ethylene, tetraphenylmethane, and hexaphenylbenzene. 
     
     
       5. The nitrogen-containing heterocyclic polymers according to any one of  claims 2 to 4 , wherein:
 the acid catalyst is one or more combinations of trifluoromethanesulfonic acid, trifluoroacetic acid, acetic acid, trichloroacetic acid, methylsulfonic acid, pentafluoropropionic acid, heptafluorobutyric acid, and perfluorosulfonic acid resin. 
 
     
     
       6. Quaternary ammonium salt polymers, a difference between a structure of the quaternary ammonium salt polymers and the nitrogen-containing heterocyclic polymers as claimed in  claim 1  is: a nitrogen-containing heterocyclic ring of the quaternary ammonium salt polymers is one of structures of quaternary ammonium nitrogen heterocyclic rings as follows: 
       
         
           
           
               
               
           
         
         R 4  is any one of methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, cyclopropyl group, isopropyl group, isobutyl group, tert-butyl group, cyclopentyl group, cyclohexyl group, and N, N, N-trimethylpentamine group. 
       
     
     
       7. Quaternary ammonium cross-linked polymers prepared by following method, wherein:
 in presence of alkali or no alkali, a quaternized cross-linking reaction is carried out between the nitrogen-containing heterocyclic polymers as claimed in  claim 1  and a polyhalogenated compound, and nitrogen sites involved in the quaternized cross-linking reaction accounted for 0.001-10% of all nitrogen sites; after the reaction is completed, partial ammoniated cross-linked intermediate polymers are obtained, and then, remaining nitrogen sites of the intermediate polymer undergo quaternization without crosslinking reaction with a monohalogenated compound, to obtain the quaternary ammonium crosslinked polymers; 
 or in presence of alkali or no alkali, a quaternized reaction without cross-linking is carried out between the nitrogen-containing heterocyclic polymers as claimed in  claim 1  and a monohalogenated compound, and nitrogen sites participating in the quaternized reaction without cross-linking accounted for 0.90-99.999% of all nitrogen sites; after the reaction is completed, partial quaternized intermediate polymers are obtained; a quaternized cross-linking reaction is carried out between remaining nitrogen sites of the intermediate polymers and a polyhalogenated compound, to obtain the quaternary ammonium crosslinked polymers; 
 or in presence of alkali or no alkali, a quaternized cross-linking reaction is carried out between the nitrogen-containing heterocyclic polymers as claimed in  claim 1 , a polyhalogenated compound and a monohalogenated compound at the same time, and nitrogen sites participating in the quaternized cross-linking reaction account for 0.001-10% of all nitrogen sites; after the reaction is completed, the quaternary ammonium crosslinked polymers are obtained; and 
 the polyhalogenated compound is selected from one or more combinations of following structures: 
 
       
         
           
           
               
               
           
         
         wherein, Y is F, Cl, Br or I, and n is an integer between 0 and 12; and 
         the monohalogenated compound is one or more combinations of iodomethane, iodoethane, iodopropane, iodobutane, iodopentane, iodohexane, iodoheptane, iodooctane, iodononane, iododecane, bromomethane, bromoethane, bromopropane, bromobutane, bromopentane, bromohexane, bromoheptane, bromooctane, bromononane, bromodecane, cyclopropyl iodine, isopropyl iodine, isobutyl iodine, cyclopentyl iodine, cyclohexyl iodine and (5-bromopentyl) trimethylammonium bromide; and 
         the alkali is one or more combinations of sodium bicarbonate, potassium bicarbonate, cesium bicarbonate, sodium carbonate, potassium carbonate, cesium carbonate, calcium carbonate, sodium hydroxide, potassium hydroxide, calcium oxide, calcium hydroxide, trimethylamine, triethylamine, N, N-dimethylethylenediamine and N, N-diisopropylethylamine. 
       
     
     
       8. A polymer flat membrane, wherein prepared by following method:
 dissolving any one or more of the nitrogen-containing heterocyclic polymers as claimed in  claim 1 , the quaternary ammonium salt polymers as claimed in  claim 6 , and the quaternary ammonium crosslinked polymers as claimed in  claim 7  in an organic solvent, obtaining a polymer solution; 
 or dissolving at least one of the nitrogen-containing heterocyclic polymers as claimed in  claim 1  and the intermediate polymers as claimed in  claim 7  in an organic solvent with the monohalogenated compound and/or the polyhalogenated compound, obtaining a polymer solution; and 
 casting or moulding the polymer solution onto a substrate, drying to obtain the polymer flat membrane; and 
 the organic solvent is one or more combinations of dimethyl sulfoxide, N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, tetrahydrofuran, chloroform, dichloromethane, toluene, ethylbenzene, xylene, and ethyl acetate; and 
 the substrate is a glass sheet, a copper sheet, an iron sheet, a ceramic sheet, a polytetrafluoroethylene sheet, a polyethylene terephthalate membrane, a polyamide membrane, a polytetrafluoroethylene membrane, a polyethylene membrane, a polypropylene membrane, a polyimide membrane, a carbon fiber membrane, or a glass fiber membrane. 
 
     
     
       9. A proton exchange membrane, wherein prepared by following method:
 soaking the polymer flat membrane as claimed in  claim 8  in phosphoric acid aqueous solution, a concentration of the phosphoric acid aqueous solution is 0.1-20M, and a soaking temperature is 0-90° C., to obtain the proton exchange film.